Solar cell technology has always shown promise as a source
of renewable energy but relatively low efficiency levels and high costs have
kept it out of the mainstream energy market. The United States Department of
Energy (DOE) has announced that with the help of government funding,
Boeing-Spectrolab has demonstrated a concentrator solar cell with a
record-breaking 40.7% efficiency
rating.

With concentrator solar cells, sunlight is intensified with
the use of an optical concentrator. This allows for more electricity to be
extracted out of each solar cell. Also employed are multi-junction solar cell
structures which allow more of the solar spectrum to be captured by using
multiple layers per cell. Each layer in a cell is then able to capture a
segment of sunlight allowing for more efficient electricity production.

“Reaching this milestone heralds a great achievement for the
Department of Energy and for solar energy engineering worldwide. We are
eager to see this accomplishment translate into the marketplace as soon as
possible, which has the potential to help reduce our nation’s reliance on
imported oil and increase our energy security,” said Assistant Secretary
Karsner.

With this new technology, the DOE is projecting that
installation costs for these types of solar cells would drop to $3 per watt with electricity costing 8 to 10 cents per kWh. The long-term goal is to have
solar energy technology installed in as many as two million American homes
providing power at 5 to 10 cents per kWh by the year 2015.

"There's no chance that the iPhone is going to get any significant market share. No chance." -- Microsoft CEO Steve Ballmer